The invention is related to bedsheets and more particularly to bedsheets known as fitted sheets, which are adapted to partially enclose a mattress and to be held neatly in position on the mattress.
In order to apply and remove fitted sheets from a mattress, it is usually necessary to fold or distort the mattress considerably, particularly at the corners, which requires a considerable amount of effort and labor. Moreover, there is a tendency for a sheet to rip due to the great amount of strain caused by fitting the sheet over and removing it from the corners of the mattress. This problem has been addressed in U.S. Pat. No. 3,114,156 to J. L. Cobb, and assigned to the assignee herein. The Cobb design teaches the use of a triangular elastic gusset near each of the corners of retaining flaps disposed on the underside of the mattress when the sheet is in place. However, portions of the retaining flaps intermediate the triangular gussets must be manually tucked and pulled when the sheet is applied in order to eliminate wrinkles and bunching of the fabric. This problem has been helped somewhat by elastic sewn to the margins of the flaps along the short side of the sheet and partially along the long side. However, problems of alignment and bunching persist.
An even more troublesome problem with fitted sheets occurs because not all mattresses of the same nominal size (i.e., twin, double, queen and kind, etc.) are the same thickness. Mattresses in each of the aforementioned nominal sizes may vary, according to cost, from thickness as of about 6 inches to about 10 inches. It is difficult to make a conventional fitted sheet which will fit all the different mattress sizes in the nominal group.
Shallow or thin mattresses do not pull the sheet, and even with extensive tucking, the sheet will sag and wrinkle and hang loosely on the bed. High or thick mattresses (and box springs) require extra material so that the sheet does not pull out from the underside of the mattress. Also, difficulty has been experienced in applying a sheet to a thick mattress for just such a reason. Consequently, if the seam length, for the thickness of the mattress, is too short, one cannot get the sheet to fit on the mattress cover, for example, a 7 inch seam on a 9 inch thick mattress. If the seam is too long, the sheet sags, or wrinkles and does not lie smoothly on the bed.
Yet another problem with fitted sheets is the difficulty of preventing bunching in the corners, causing the formation of "ears" by the bunched material. This can occur especially when applying the sheet to a thin mattress.
The fitted sheet of the present invention is adapted to be easily applied on a mattress (or box springs) of a selected nominal size regardless of the thickness variations in such size. The sheet is adapted to be easily applied and to fit flatly on the mattress without bunching at the corners or along the sides and without sagging or forming wrinkles.